Last year's runner-up Garbine Muguruza is into the fourth round with a 6-1, 6-1 win over Kazakhstan's Zarina Diyas in 58 minutes.
Muguruza was simply too good for her unseeded opponent, ruthlessly breaking a total of five times with Diyas having no answer to the onslaught.
The two-time major champion will play Naomi Osaka in the next round.
With Osaka and Barty out, who will win gold in wide-open women's draw?
MUGURUZA: I PLAYED SMARTER
'I played a little bit smarter' - Muguruza's post-match interview
"I felt good out here,” she said post-match. "We played a year ago and it was a really tough match so I’m happy.
"I played a little bit smarter than last time and I could win in two sets.
"I know people think very far for us it is just about match after match. That is how you get to the last rounds you cannot think too far ahead.
"I have one match after another and I have to win each time I come out on court. I think I played well and we won it my team and I so we’re going to try our best.”
- - -
A head-turning offer for head-turning tennis. One-month premium subscription for just 99p on the Eurosport app and eurosport.co.uk.
Osaka, Barty, Watson begin bid for Olympic tennis glory this weekend
Inspired Jabeur stuns Muguruza in Wimbledon thriller